Bridging the gap: solving spatial means-ends relations in a locomotor task.

Using a means-means-ends problem-solving task, this study examined whether 16-month-old walking infants (N = 28) took into account the width of a bridge as a means for crossing a precipice and the location of a handrail as a means for augmenting balance on a narrow bridge. Infants were encouraged to cross from one platform to another over narrow and wide bridges located at various distances from a wooden handrail. Infants attempted to walk over the wide bridge more often than the narrow one and when the handrail was within reach. Infants demonstrated parallel problem solving by modifying exploratory behaviors and bridge-crossing strategies that simultaneously accounted for the spatial and functional relations between body and bridge, body and handrail, and bridge and handrail.